The present invention is concerned with a novel preparation of methyl vanillyl ketone from guaiacol.
Methyl vanillyl ketone has the formula: ##STR1## It is an intermediate in the preparation of the hypertensive agent, L-.alpha.-methyl-3,4-dihydroxyphenylalanine. The ketone (I) can be prepared from the substituted benzaldehyde, vanillin, or from a suitably substituted phenyl acetonitrile. These processes and/or the preparation of the hypertensive agent are disclosed in U.S. Pat. Nos. 3,344,023 and 3,366,679. Of the two known processes for preparing the ketone (I), the preferred process utilizes the vanillin starting material. Vanillin is expensive and an alternate route to the ketone (I) using a less expensive, readily available starting material has been sought.
The present process provides such a process, using guaiacol, having the formula ##STR2## as the starting material.